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A166003
Primes p such that p+-1, p+-2 and p+-3 are not squarefree.
5
47527, 186247, 218527, 245149, 269953, 377543, 390449, 432277, 447823, 453053, 469649, 518123, 568177, 584911, 589273, 606323, 632347, 661547, 761347, 831751, 848213, 897577, 913327, 925949, 952253, 1172351, 1205647, 1220347, 1241477
OFFSET
1,1
LINKS
MATHEMATICA
f[n_]:=Max[Last/@FactorInteger[n]]; q=2; lst={}; Do[p=Prime[n]; If[f[p-3]>=q&&f[p-2]>=q&&f[p-1]>=q&&f[p+1]>=q&&f[p+2]>=q&&f[p+3]>=q, AppendTo[lst, p]], {n, 6*8!}]; lst
Select[Prime[Range[100000]], NoneTrue[#+{-3, -2, -1, 1, 2, 3}, SquareFreeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Apr 17 2018 *)
KEYWORD
nonn
AUTHOR
EXTENSIONS
Edited by N. J. A. Sloane, Oct 04 2009
STATUS
approved